CSAMT investigations in the faulted basin geothermal field, Shanxi, China

Abstract

The CSAMT (controlled source audio magnetotelluric) method was applied to Shanxi faulted basin, yuci. The major purpose of this CSAMT (frequencies ranged from 0.125 to 8192 Hz) survey is to locate the active hydrothermal system. The results of the 1D and 2D CSAMT inversion indicate the following: 1.electrical terms can be divided into four ranges of resistivity values: 1). A conductor layer (0∼40Ω.m), which is characteristic of silty clay and fine sandstone in the Neozoic (N) and Quaternary (Q); 2). The first Moderate resistive (40∼200Ωm) indicate mudstone in the Triassic system in terms of water content in; 3) The second Moderate resistive (200 ∼ 600Ωm) indicate sandy shale in the Carboniferous and Permian; 4) The last resistive(>600Ω.m) layer obtained for all models is typical for Limestone in Ordovician. 2. The boundary between the third layer and four layers can be interpreted as a mark of the top of the active hydrothermal system.